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Improving the Performance of Oilwell Cement by Graft-modifi ed PB Latex

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Transactions of Tianjin University 2018年第5期24卷 434-441页

作者： Jintang Guo Wenjie Pan Jinjie Fan Yongjin Yu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Drilling Research Institute of CNPC Beijing 100089China

Graft-modified polybutadiene(PB) latex was synthesized and used as an admixture to improve the performance of oilwell cement. Results showed that the addition of latex to pure cement slurry can significantly reduce the fluid loss of the cement slurry. When the dosage was 8%, the fluid loss was only 38 mL, and the fluidity of the cement slurry was improved. With an increasing amount of latex, the fluidity of the cement slurry increased continuously. The toughness of cement was significantly enhanced, whose average elastic modulus was 4.2 GPa. Scanning electron microscopy revealed that the filter cake of the cement slurry with latex was thin and dense, and the surface was coated with a layer of latex film. The microstructure of the cement stone showed a high density, and an interweaving mesh network formed in the cement. The results of cement hydration heat analysis and X-ray diffraction showed that latex inhibited the hydration of cement; the effect was stronger under a larger amount of latex. It is indicated that the graft-modified PB latex has great potential to replace the conventional styrene-butadiene rubber(SBR) latex for cementing in the future.

关键词： Graft-modifi ed PB latex Fluid loss Fluidity Toughness Cement hydration

Long-term testosterone supplementation is useful for ed Nith testosterone deficiency

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Asian Journal of Andrology 2013年第5期15卷 699-700页

作者： Tao Jiang Lei Zheng Xiao-Ming Su Jin-Qiang Peng Dong-Chen Sun Quan-Lin Li Zhi-Wei Zhang Fa-Peng Wang Hui Jiang Department of Urology First Affiliated Hospital of Dalian Medical University Dalian 116011 China Department of Urology Peking University Third Hospital Beijing 100191 China

Dear editor, We present an interesting case of a patient with erectile dysfunction （ed） and testosterone deficiency （TD） who was treated with testoster- one supplementation therapy （TST） in combination with sildenafil for 45 months. The patient continued to respond well even after the discontinuation of sildenafil for 8 months. Major side effects and complications were not reported at the long-term follow-up.

关键词： Long-term testosterone ed testosterone deficiency

Testing and analysis of the plastic scintillator units for LHAASO-ed

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Radiation Detection Technology and Methods 2021年第4期5卷 513-519页

作者： Ya-Ping Wang Chao Hou Xiang-Dong Sheng Shao-Hui Feng Hong-Kui Lv Jia Liu Jing Zhao Xiao-Peng Zhang Quan-Bu Gou Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China TIANFU Cosmic Ray Research Center ChengduSichuanChina

Background A total of 5195 electromagnetic particle detectors(eds)are used in the 1-square-kilometer extensive air shower array(KM2A),which is a subarray of the Large High Altitude Air Shower Observatory(LHAASO).Purpose As the detection sensitive medium of the eds,more than 20,000 plastic scintillator units(BC-408),produced by Saint-Gobain,are used in *** is important to monitor the light output of the scintillator units among the *** To improve the efficiency,a sampling inspection scheme(misjudgment rate of less than 5%)was designed,and a batch test system was *** units of scintillator units can be measured at a *** test system selects the single muon events of cosmic rays to measure the light output values of the plastic scintillator *** The measurement has an uncertainty of less than 2%.By pretest calibration,the difference between different channels can be *** calibration was implemented approximately every 3 months,and the test system had been running stably for 28 *** measuring the ratio of the signals of selected far and near probe events,the changes in the quality of different batches of plastic scintillator units can be *** The test system realized accurate measurement of the light output,and all batches satisfied the requirements of the experiment.

关键词： LHAASO ed Plastic scintillator unit Light output

Evaluation of modifi ed Alvarado scoring system and RIPASA scoring system as diagnostic tools of acute appendicitis

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World Journal of Emergency Medicine 2017年第4期8卷 276-280页

作者： Abdullah Shuaib Ali Shuaib Zainab Fakhra Bader Marafi Khalid Alsharaf Abdullah Behbehani Department of Surgery Kuwait Mubarak Alkabeer Hospital Jabriya Kuwait Biomedical Engineering Unit Physiology Department Faculty of Medicine Kuwait University Kuwait City Kuwait MD in internship year Kuwait Institute of Medical Specialization Kuwait City Kuwait Department of Surgery Faculty of Medicine Kuwait University Kuwait City Kuwait

BACKGROUND: Acute appendicitis is the most common surgical condition presented in emergency departments worldwide. Clinical scoring systems, such as the Alvarado and modified Alvarado scoring systems, were developed with the goal of reducing the negative appendectomy rate to 5%–10%. The Raja Isteri Pengiran Anak Saleha Appendicitis(RIPASA) scoring system was established in 2008 specif ically for Asian populations. The aim of this study was to compare the modif ied Alvarado with the RIPASA scoring system in Kuwait ***: This study included 180 patients who underwent appendectomies and were documented as having "acute appendicitis" or "abdominal pain" in the operating theatre logbook(unit B) from November 2014 to March 2016. The sensitivity, specificity, positive predictive value(PPV), negative predictive value(NPV), diagnostic accuracy, predicted negative appendectomy and receiver operating characteristic(ROC) curve of the modified Alvarado and RIPASA scoring systems were derived using SPSS statistical ***: A total of 136 patients were included in this study according to our criteria. The cut-off threshold point of the modif ied Alvarado score was set at 7.0, which yielded a sensitivity of 82.8% and a specif icity of 56%. The PPV was 89.3% and the NPV was 42.4%. The cut-off threshold point of the RIPASA score was set at 7.5, which yielded a 94.5% sensitivity and an 88% specif icity. The PPV was 97.2% and the NPV was 78.5%. The predicted negative appendectomy rates were 10.7% and 2.2% for the modif ied Alvarado and RIPASA scoring systems, respectively. The negative appendectomy rate decreased significantly, from 18.4% to 10.7% for the modified Alvarado, and to 2.2% for the RIPASA scoring system, which was a signif icant difference(Ped on the results of this study, the RIPASA score is a simple scoring system with better sensitivity and specif icity than the modif ied Alvarado scoring system in A

关键词： Acute appendicitis Modifi ed Alvarado score RIPASA score

智能变电站IEC 61850 ed 2.0工程配置应用方案

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电力系统自动化 2018年第2期42卷 154-159页

作者：李金胡荣王丽华王志华中国南方电网电力调度控制中心广东省广州市510530 北京四方继保自动化股份有限公司北京市100085

IEC 61850第2版(ed 2.0)对系统集成配置过程进行了重大改进,包括新增实例化的智能电子设备描述(instantiated Ied description,IID)文件和系统交换描述(Sed)文件,加强配置工具约束,引入分项目管理方法。论文根据当前智能变电站IEC 6185... 详细信息

IEC 61850第2版(ed 2.0)对系统集成配置过程进行了重大改进,包括新增实例化的智能电子设备描述(instantiated Ied description,IID)文件和系统交换描述(Sed)文件,加强配置工具约束,引入分项目管理方法。论文根据当前智能变电站IEC 61850工程配置实际需求,对IEC 61850ed 2.0工程配置过程改进的工程实用性进行深入分析。提出IEC 61850ed 2.0配置过程工程化应用方案,包括变电站配置描述(SCD)文件配置过程改进方案和工程分项目管理方案,并给出典型应用示例。

关键词： IEC 61850 ed 2.0 配置调试过程分项目管理 IID文件 Sed文件

Erectile Dysfunction (ed) within Hospital Facilities in Cotonou

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Open Journal of Urology 2017年第3期7卷 65-74页

作者： Natchagande Gilles Avakoudjo Dedjinin Georges Josue Yevi Ines Dodji Magloire Agounkpe Michel Michael Kaka Mahamane Adama Salissou Sossa Jean Hodonou DetondjiFred Jacquet Djamal Soumanou Fouad Hounnasso Prince Pascal CNHU-HKM Urology-Andrology University Clinic CotonouRepublique of Benin

Introduction: Erectile dysfunction (ed) is defined as the persistent inability to achieve the necessary degree of erection for sexual activity. It is a common disease which can significantly affect the quality of life of sufferer and their partners. The purpose of this study is to give an overview of the magnitude of this medical condition in Benin society. Material and Method: It was a multicenter cross-sectional descriptive and analytical study conducted over a period of one month from 1st to 30th June 2015. A questionnaire was prepared for this purpose. Outcomes: The average age in this series is 48.32 with extremes ranging from 18 to 95 years. These patients were predominantly public servants. All our patients (100% of the study population) responded to the single question of John. B. Mckinlay. The global ed prevalence was 52.6%. The multivariate analysis helped to identify a correlation with several factors associated with ed. These factors included: age, occupation, lifestyle, etc. 41.91% of patients with ed and/or other sexual disorders declared “not at all acceptable” to continue living with these disorders. The patients benefitted from different treatments including IPDE-5 and traditional treatment in respectively 32.8% and 40.1% of cases. Conclusion: ed is a condition in its own which has an impact on the patients’ quality of life. Its discovery may lead to the diagnosis of cardiovascular, hormonal or neurological diseases.

关键词： ed Sexual Disorder Sexuality

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ed与SVD及相关阵中信号的提取

华东工学院学报 1991年第3期 45-49页

作者：王凤振华东工学院电子工程系

本文介绍信号相关矩阵的奇异值分解(SVD)与特征根结构分解(ed)之间的关系及用信号特征矢量表示平稳随机过程和信号子空间的方法。利用信号子空间对信号进行信息提取,可减少噪声对估计参数精度的影响。文中论述了提高前向预测定向精度的... 详细信息

本文介绍信号相关矩阵的奇异值分解(SVD)与特征根结构分解(ed)之间的关系及用信号特征矢量表示平稳随机过程和信号子空间的方法。利用信号子空间对信号进行信息提取,可减少噪声对估计参数精度的影响。文中论述了提高前向预测定向精度的方法。SVD能把信号空间与噪声空间分开,以提出互相关矩阵中信号信息。

关键词：信号处理 ed SVD 相关矩阵

Journal of Donghua University (Eng . ed .)Contents of Volume 21

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Journal of Donghua University(English edition) 2004年第6期 156-162页

Approaches to Greek Myth, Lowell edmunds (ed.), Baltimore and London 1990

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Journal of Ancient Civilizations 2007年 141-148页

作者： Wang Shaohui, IHAC

"With the possible exception of the Vedic-Hindu religion of India, the religion or religions associated with the ancient Greeks produced the world’s most complex and sophisticated mythology." ’ On the basis of this,... 详细信息

关键词： Greek ed Baltimore and London 1990 Approaches to Greek Myth